ETS-VIII

JAXA Engineering Test Satellite ETS-VIII (Kiku 8) is the eighth technology test satellite in a series which started with ETS-1 in 1975 by NASDA. It was launched with the H-2A on December 18, 2006. ETS-VIII was developed by JAXA in cooperation with NICT and NTT. The aim of ETS-VIII is to enable satellite communications with small terminals. Unlike the Iridium satellites for mobile communication, ETS-VIII is positioned at GEO. However to fulfill the task the satellite must carry two very large antennas. So far, this has been the only use of the 204 configuration (four strap-on boosters) of the H-IIA launch vehicle.

Timetable

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Äetsä

Äetsä is a former municipality of southwestern Finland. The municipality was founded on 1981 when municipalities of Keikyä and Kiikka were consolidated to a single municipality.

On 1 January 2009, it was consolidated with the municipalities of Vammala and Mouhijärvi to form a new city of Sastamala.

Geography

Äetsä was located in the western Pirkanmaa region, and was part of the former (1997 to 2010) province of Western Finland.

The municipality had a population of 4,797 (November 30, 2008) and covered an area of 241.95 square kilometres (93.42 sq mi), of which 8.38 km² (3.24 sq mi) was water. The population density was 20.54 inhabitants per square kilometre (53.2/sq mi).

The municipality was unilingually Finnish.

External links

Coordinates: 61°17′05″N 022°41′50″E / 61.28472°N 22.69722°E / 61.28472; 22.69722

ETS2

Protein C-ets-2 is a protein that in humans is encoded by the ETS2 gene. The protein encoded by this gene belongs to the ETS family of transcription factors.

Interactions

ETS2 has been shown to interact with:

References

Further reading

External links

ETS1

Protein C-ets-1 is a protein that in humans is encoded by the ETS1 gene. The protein encoded by this gene belongs to the ETS family of transcription factors.

Function

There are 28 ETS genes in humans and 27 genes – in mice. They bind the DNA via their winged-helix-turn-helix DNA binding motif known as the Ets domain that specifically recognizes DNA sequences that contain a GGAA/T core element. However, Ets proteins differ significantly in their preference for the sequence flanking the GGAA/T core motif. For instance, the consensus sequence for Ets1 is PuCC/a-GGAA/T-GCPy. On the other hand, many natural Ets1-responsive GGAA/T elements differ from this consensus sequence. The later suggests that several other transcription factors may facilitate Ets1 binding to unfavorable DNA sequences.

Ets1 binds to DNA as a monomer. Phosphorylation of serine residues of the C-terminal domain (in the nucleotide sequence they belong to exon VII) known as autoinhibition makes Ets1 inactive. There are several ways to activate Ets1. First, Ets1 can be dephosphorylated. Second, two Ets1 can be activated If two Ets molecules homodimerize. The homodimerization occurs if DNA binding sites are present in the correct orientation and spacing. Thus, the exact layout of binding sites within an enhancer or promoter segment to either relieve or allow autoinhibition of Ets1 to occur may strongly influence whether or not Ets1 actually binds to particular site. Third, Ets1 can be activated by Erk2 and Ras at Thr38. The truncated isoform cannot be phosphorylated by the Erk2. It is localized in the cytoplasm and acts as a dominant negative isoform. Contrary, another isoform that misses exon VII is constitutively active. Many Ras responsive genes harbor combinatorial Ets/AP1 recognition motifs through which Ets1 and AP1 synergistically activate transcription when stimulated by Ras.

Comet Ikeya–Seki

Comet Ikeya–Seki, formally designated C/1965 S1, 1965 VIII, and 1965f, was a long-period comet discovered independently by Kaoru Ikeya and Tsutomu Seki. First observed as a faint telescopic object on September 18, 1965, the first calculations of its orbit suggested that on October 21, it would pass just 450,000 km above the Sun's surface, and would probably become extremely bright.

Comets can defy such predictions, but Ikeya–Seki performed as expected. As it approached perihelion observers reported that it was clearly visible in the daytime sky next to the Sun. In Japan, where it reached perihelion at local noon, it was seen shining at magnitude −10. It proved to be one of the brightest comets seen in the last thousand years, and is sometimes known as the Great Comet of 1965.

The comet was seen to break into three pieces just before its perihelion passage. The three pieces continued in almost identical orbits, and the comet re-appeared in the morning sky in late October, showing a very bright tail. By early 1966, it had faded from view as it receded into the outer solar system.

Comet Humason

Comet Humason, formally designated C/1961 R1 (a.k.a. 1962 VIII and 1961e), was a non-periodic comet discovered by Milton L. Humason on September 1, 1961. Its perihelion was well beyond the orbit of Mars, at 2.133 AU. Its period is 2940 years, and the diameter of its nucleus estimated at about 41 km.

It was a 'giant' comet, much more active than a normal comet for its distance to the Sun, with an absolute magnitude of +1.5, a hundred times brighter than an average new comet. It had an unusually disrupted or 'turbulent' appearance. It was also unusual in that the spectrum of its tail showed a strong predominance of the ion CO+, a result previously seen unambiguously only in Comet Morehouse (C/1908 R1).

References

8 (number)

8 (eight /ˈeɪt/) is the natural number following 7 and preceding 9.

In mathematics

8 is: